Related papers: Variational calculation of 4He tetramer ground and…
In a previous work [Phys. Rev. A 85, 022502 (2012)] we calculated, with the use of our Gaussian expansion method for few-body systems, the energy levels and spatial structure of the 4He trimer and tetramer ground and excited states using…
Four-body systems are studied using an effective field theory with two- and three-body contact interactions. A method to systematically address deep trimers (three-body bound states that are more tightly bound than four-body bound/resonant…
The four-boson universality suggests the existence of the second excited tetramer state in a system of cold ${}^4\mathrm{He}$ atoms. It is not bound but could be seen as a resonance in the atom-trimer scattering. This process is rigorously…
We calculate the universal spectrum of trimer and tetramer states in heteronuclear mixtures of ultracold atoms with different masses in the vicinity of the heavy-light dimer threshold. To extract the energies, we solve the three- and…
The momentum-space structure of the Faddeev-Yakubovsky (FY)components of weakly-bound tetramers is investigated at the unitary limit using a renormalized zero-range two-body interaction. The results, obtained by considering a given trimer…
We consider the non-relativistic four-boson system with short-range forces and large scattering length in an effective quantum mechanics approach. We construct the effective interaction potential at leading order in the large scattering…
Faddeev-Yakubovski equations are solved numerically for 4He tetramer and trimer states using realistic helium-helium interaction models. We describe the properties of ground and excited states, and we discuss with a special emphasis the…
We calculated, using seven realistic 4He-4He potentials in the literature, the Efimov spectra of the 4He trimer and tetramer and analyzed the universality of the systems. The three-(four-)body Schroedinger equations were solved fully…
We propose a novel mathematical approach for the calculation of near-zero energy states by solving potentials which are isospectral with the original one. For any potential, families of strictly isospectral potentials (with very different…
The strong short-range repulsion, characteristic to realistic interatomic potentials, complicates the description of weakly-bound few-body systems such as those of \He atoms. The present work proposes an approach for solving this problem…
A method of direct solution of the Faddeev equations for the bound-state problem with zero total angular momentum is used to calculate the binding energies. The results for binding energies of He$_2$$^6$Li and He$_2$$^7$Li systems and…
We extend the Eckart theorem, from the ground state to excited statew, which introduces an energy augmentation to the variation criterion for excited states. It is shown that the energy of a very good excited state trial function can be…
The ^3He^4He_2 three-atomic system is studied on the basis of a hard-core version of the Faddeev differential equations. The binding energy of the ^3He^4He_2 trimer, scattering phase shifts, and the scattering length of a ^3He atom off a…
Long-range bound states of the excited heteronuclear 3He*--4He* system that dissociate to either 3He(1s2s 3S_1) + 4He(1s2p 3P_j) or 3He(1s2p 3P_j) + 4He(1s2s 3S_1), where j=0, 1, 2, are investigated using both single-channel and…
The ^4He_3 bound states and the scattering of a ^4He atom off a ^4He dimer at ultra-low energies are investigated using a hard-core version of the Faddeev differential equations. Various realistic ^4He-^4He interactions were employed, amomg…
The method of group theory is applied to investigate the ground and the excited states of the triton and helium nuclei by using the translation invariant shell model with basis functions corresponding to even number of quanta of excitations…
We apply a hard-core version of the Faddeev differential equations to the ^3He^4He_2 three-atomic system. Using these equations we calculate the binding energy of the ^3He^4He_2 trimer with the LM2M2 potential by Aziz and Slaman and more…
The ground and excited states of the 3H and 4He nuclei are studied in the framework of group-theoretical methods. Basis functions of the unitary scheme model corresponding to even numbers of quanta of excitation in the range from zero to…
We report a variational calculation of ground state energies and radii for 4He_N droplets (3 \leq N \leq 40), using the atom-atom interaction HFD-B(HE). The trial wave function has a simple structure, combining two- and three-body…
A very accurate, (HF)$_2$ potential energy surface (PES) due to Huang et al. (J. Chem. Phys., 150, 154302 (2019)) is used to calculate the energy levels of the HF dimer by solving the nuclear-motion Schr\"{o}dinger equation using…